As there begins to be an increased need for the development of renewable energy sources, the large scale production of algal bio-mass as means to produce a transportation fuel is becoming a highly sought after solution. Thus numerous ventures around the world have been organized to solve this problem. However, growing mass amounts of algae cheaply is difficult, and there are many obstacles that have to be overcome, with one of the major ones being frequent contamination events.
Thus the need to design a photo-bioreactor, which can grow a robust axenic culture, has become very apparent. When designing an effective solution, one also has to consider the many other contributing factors, such as energy balance, environmental impact, overall production rates, ease of harvest, capital expense, operating expense and, of course, sterility. An important factor for anyone attempting to develop a renewable fuel is keeping the overall energy balance of the production system positive, while allowing the system to function optimally. A major energy sink for most photo-bioreactor systems is the need for a cooling system. Maintaining an optimum temperature range (25° C.-39° C.) is crucial for the micro-organisms survival. Another factor that affects the energy balance of the system is the need for efficient CO2 uptake. Being that CO2 is an essential input to the production of autotrophic organisms it becomes an expensive commodity to waste if it's not over 90 percent utilized within the reactor.